Light emitting display device and method for manufacturing the same

• US 10,025,158 B2
• Filed: 06/27/2016
• Issued: 07/17/2018
• Est. Priority Date: 03/09/2016
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: BOE Technology Group Co., Ltd.
• Inventors: Kristal, Boris
• Primary Examiner(s): Ben, Loha
• Application Number:
  US15/525,863
• Publication Number:
  US 20180074381A1
• Time in Patent Office: 750 Days
• Field of Search: 359245, 359263, 359298, 359315, 359318, 359385, 359630, 257E33001, 257E33013, 257 64, 257 98, 257107, 257163-165, 438 22, 438 28, 438 29, 438 34, 438758, 438760, 349 11, 349 15, 349 16
• CPC Class Codes: G02F 1/23 for the control of the colour G02F1/03 - G02F1/21 take precedence
• CPC Class Codes: G02F 1/29 for the control of the position or the direction of light beams, i.e. deflection
• CPC Class Codes: G02F 2201/12 electrode
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G02F 2201/34 reflector
• CPC Class Codes: G02F 2203/01 transmissive
• CPC Class Codes: G02F 2203/02 reflective
• CPC Class Codes: G02F 3/02 Optical bistable devices
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1259 Multistep manufacturing methods
• CPC Class Codes: H10K 50/856 comprising reflective means
• CPC Class Codes: H10K 59/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/50 OLEDs integrated with light modulating elements, e.g. with electrochromic elements, photochromic elements or liquid crystal elements

Abstract

Embodiments of the present disclosure relate to a light emitting display device and a method for manufacturing the same. The light emitting display device comprises one or more pixel units, each of which is provided with a transparent light emitting device on a substrate, wherein at least a part of the pixel units are provided with a switchable mirror, which is located between the substrate and the light emitting device and is switchable between a transmission mode and a reflection mode.

Claims

1. A light emitting display device comprising one or more pixel units, each of which is provided with a transparent light emitting device on a substrate, wherein

at least one of the pixel units is provided with a switchable mirror, which is located between the substrate and the light emitting device and is switchable between a transmission mode and a reflection mode.

2. The light emitting display device according to claim 1, wherein the switchable mirror is a metal-hydride switchable mirror.

3. The light emitting display device according to claim 2, wherein the switchable mirror comprises a bottom transparent electrode, a hydrogen storage electrode, a proton conducting layer, an active layer switchable between a metallic reflection state and a metal hydride transmission state, and a sealing layer, which are stacked from bottom to top, wherein the proton conducting layer and the sealing layer are connected with each other.

4. The light emitting display device according to claim 1, wherein the switchable mirror comprises a bottom transparent electrode, a hydrogen storage electrode, a proton conducting layer, an active layer switchable between a metallic reflection state and a metal hydride transmission state, and a sealing layer, which are stacked from bottom to top, wherein the proton conducting layer and the sealing layer are connected with each other.

5. The light emitting display device according to claim 4, further comprising a first switching transistor, a drain electrode of which is connected with the bottom transparent electrode, for controlling the switchable mirror to switch between the transmission mode and the reflection mode.

6. The light emitting display device according to claim 5, further comprising a second switching transistor, a drain electrode of which is connected with a pixel electrode of the light emitting device, for controlling whether to provide a data signal to the light emitting device.

7. The light emitting display device according to claim 4, wherein the hydrogen storage electrode is made of a hydrogen storage alloy selected from at least one of WO₃, NdMgNi_4-aCo_a, Ti_0.5Al_0.25Ni_0.25 and ZrMn_wM_xCr_yNi_z, wherein

in NdMgNi_4-aCo_a, a is in a range of 0-1.0;

and

in ZrMn_wM_xCr_yNi_z, M is V or Mo, 0.6≤

w≤

0.8, 0.1≤

x≤

0.3, 0<

y≤

0.2, and 1.2≤

z≤

1.5.

8. The light emitting display device according to claim 4, wherein the proton conducting layer and the sealing layer are made of a proton conducting material selected from at least one of ZrO₂, SrCeO₃, BaCeO₃ and BaZrO₃, and wherein H⁺ is capable of being filled in pores of the proton conducting material.

9. The light emitting display device according to claim 4, wherein the active layer is made of a material selected from at least one of GdMg, Mg₂Ni, YMg and LaMg.

10. The light emitting display device according to claim 1, wherein the switchable mirror and the light emitting device are arranged to be directly opposite to each other.

11. The light emitting display device according to claim 10, wherein a planarization layer is arranged between the switchable mirror and the light emitting device such that the switchable mirror and the light emitting device are directly opposite to each other.

12. The light emitting display device according to claim 1, wherein the switchable mirror has a thickness of 80 nm-120 nm.

13. The light emitting display device according to claim 1, wherein the light emitting device comprises a pixel electrode, a light emitting layer, and a counter electrode directly opposite to the pixel electrode stacked in sequence.

14. The light emitting display device according to claim 1, wherein each pixel unit comprises one or more subpixel units, each of which is provided with one said switchable mirror.

15. The light emitting display device according to claim 1, wherein each pixel unit is a pixel unit composed of a plurality of subpixels in different colors, and wherein the each pixel unit is provided with one said switchable mirror.

16. A method for manufacturing a light emitting display device, comprising:

forming, in at least one of pixel units on a substrate, a switchable mirror which is switchable between a transmission mode and a reflection mode; and

forming a transparent light emitting device on the switchable mirror.

17. The method for manufacturing a light emitting display device according to claim 16, wherein the forming, in at least one of pixel units on a substrate, a switchable mirror which is switchable between a transmission mode and a reflection mode comprises:

forming a bottom transparent electrode on the substrate;

forming a hydrogen storage electrode on the bottom transparent electrode;

forming a proton conducting layer on the hydrogen storage electrode;

forming, on the proton conducting layer, an active layer switchable between a metallic reflectance state and a metal hydride transmission state; and

forming a sealing layer on the active layer, wherein the proton conducting layer and the sealing layer are connected with each other.

18. The method for manufacturing a light emitting display device according to claim 17, further comprising:

forming a first switching transistor and a second switching transistor before forming the switchable mirror, wherein;

the first switching transistor and the second switching transistor are formed through a same process;

a drain electrode of the first switching transistor is connected with the bottom transparent electrode, for controlling the switchable mirror to switch between the transmission mode and the reflection mode; and

a drain electrode of the second switching transistor is connected with a pixel electrode of the light emitting device, for controlling whether to provide a data signal to the light emitting device.